The Pennsylvania School Library Project is an amazing resource for materials:
http://paschoollibraryproject.org/home

PSLA Top Ten Tips for Library Advocacy:
http://www.psla.org/advocacy/top-ten-tips/

Link to AASL Brochures
http://www.ala.org/aasl/advocacy/tools/brochures
2012 PSLA Conference offered a workshop called Speaking Out, presented by Deb Kachel and others. Check out the Marketing yourself PDF and Elevator Speeches: Friday Session A. Here's the link:
http://pslaconf.wikispaces.com/Friday+Sessions